Anchors are commonly employed during surgical procedures to provide a reliable attachment location for sutures in or against a substrate, those attached sutures then being used to capture and retain other objects, such as soft tissue. As such, the suture anchor plays an important role in attaching objects, such as soft tissue to a substrate. The substrate may be bony tissue or soft tissue. In the case of bony tissue, suture anchors are generally inserted into a pre-formed hole in the bone, so that suture extends out of the hole from the anchor. In the case of soft tissue, suture anchors generally are placed on a side of the soft tissue such that suture extends through a hole in the tissue to extend beyond the soft tissue on a side opposite the anchor.
Commonly, such suture anchors contain at least one ridged member which deforms to create an interference fit with a substrate, the interference fit creating a retention capacity of the anchor. Other suture anchors contain some external feature, such as barbs or screw threads, which interacts with the substrate, through piercing, cutting and/or deforming the substrate, to create a retention capacity. Other anchors include multiple features, such as deployable barbs, to create retention capacity.
Soft suture anchors have also been developed, such as the Biomet JuggerKnot™ (a trademark of Biomet Corporation), which utilizes a stiff braded line, which appears to function as a barb against the side of a hole in a substrate.
Many factors have a direct effect on the actual retention capacity achieved by any suture anchor. For example, the quality of tissue, bony or soft, may increase or decrease the retention capacity by a large degree depending on the design of a particular suture anchor. Similarly, the quality of installation affects the retention capacity. As evidenced by the large number of suture anchors on the market, some suture anchors perform in certain circumstances while other anchors perform better in other circumstances.
In light of the forgoing, there continues to be a need for a suture anchor that can provide a relatively more reliable retention capacity in a variety of substrates and when installed under a variety of complex conditions.